Map Morphing: Making Sense of Incongruent Maps

Map morphing is an interactive visualization technique that provides a user-controlled, animated translation from one map to another. Traditionally, overlay mechanisms are used to present layers of information over a single projection. Map morphing provides a way to relate maps with significant spatial and schematic differences. This paper presents the morphing technique and the results of a comparative evaluation of map morphing against standard ways of presenting related maps. Our results demonstrate that map morphing provides additional information that can be used to effectively relate maps. In particular, significantly more tasks were completed correctly using the morphing interface than either a windowed or an inset interface.